An emergency block valve (EBV) is used as a means of isolating flammable or toxic substances in the event of a leak or fire. The installation, and use, of EBV's in many hydrocarbon services will significantly reduce the potential of fire and explosion damages caused by loss of hydrocarbon containment situations; and a general improvement in overall plant safety for both capital assets, and operating and maintenance personnel. In hydrocarbon, and/or toxic services, EBV's will serve to mitigate the potential of significant environmental releases.
In another version of EBV, the flow of a fluid is released in case of an emergency. For example, the valve of a sprinkler system will open and release the water in the event of a fire.
Existing automatic EBVs typically are equipped with a rapid action motor pneumatic operator. Petrochemical and similar industries require periodic testing of critical valves of this nature. However, in the existing EBVs, after testing of the EBV operations, reset or rebuild will be required to make the EBV ready for service, and such reset or rebuild takes multiple persons and considerable amount of time.
Therefore, there is a need for an EBV that can be easily reset by one person to a fully operational status in a very short period of time, and that after testing, rebuilding will not be required.